When comparing C vs C++, the Slant community recommends C for most people. In the question“What is the best programming language to learn first?” C is ranked 3rd while C++ is ranked 29th. The most important reason people chose C is:
Learning C forces you to grapple with the low-level workings of your computer (memory management, pointers, etc.) in ways that the other languages abstract away. Without an understanding of these low-level aspects of computer programming you will be limited if you try to develop an application that needs to run in a memory or performance constrained environment. Other languages like Python can obscure a lot of details, so your foundation may be weaker.
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro Understanding of computers
Learning C forces you to grapple with the low-level workings of your computer (memory management, pointers, etc.) in ways that the other languages abstract away. Without an understanding of these low-level aspects of computer programming you will be limited if you try to develop an application that needs to run in a memory or performance constrained environment.
Other languages like Python can obscure a lot of details, so your foundation may be weaker.
Pro Helps with learning other languages later
A lot of languages used in the industry have a C-like syntax (C++, Java, Javascript, C#, PHP) and starting with C will help new developers to be familiar with it's syntax and by extensions with the syntax of many popular languages.
Pro Industry standard
C is the industry standard programming language, moreover, it is the most popular programming language to use. C is the language used for most Windows, UNIX and Mac operating systems.
Pro Portable
C is portable between most hardware. Generally a C compiler is made for any new architecture, and already exists for existing architectures.
C is portable between all operating systems (Windows, UNIX, Mac, etc.) and only needs a program to be recompiled to work. This allows anyone on any operating system to learn about the language and not be held back by intricacies of their operating system.
With this said, C's portability these days is not quite what it used to be. Much of said portability relies on the POSIX standard in particular, and as time passes, the compliance of a given system with that standard is becoming less certain; especially in the case of Linux. Most things will still be portable (or at least emulatable) between Windows, Linux, and FreeBSD for example; but you will at times need to make use of platform-specific support libraries and APIs as well.
Pro Must-have
Capability to program in C is greatly appreciated in developers, creates an image of competency, and many programmers will learn it at some point in their careers.
Pro Low level of abstraction
While higher level languages languages like Java and Python provide possibilities to be "more expressive" per line of code, it's much more convenient to start with "less efficient" (get me right) language, in order to get initial concepts of how things behave at lower level.
Actually C is a good starting point moving to both higher and lower levels of abstraction, the good example here would be learning C before Assembler, as for general use the Assembler quite hard to understand due to low level of its abstraction (like getting the understanding on how loops work in C before trying to implement them on Assembler).
Pro More control over the code
Pro The king of languages, imitated, extended but never equalled
Made of a small set of keywords and rules, only your imagination is the limit. Above all, when it comes to 'pro' programming, C is the only one to rely on.
Pro Teaches good practices
Writing in C will require you to understand how things are done. C implies using and understanding the fundamentals. Learning a higher-level language after is much easier.
Pro Portable between CPU architectures
C was designed to be independent of any particular machine architecture, and so with a little care, it is easy to write "portable" programs (see here). By design, C provides constructs that map efficiently to typical machine instructions, and therefore it has found lasting use in applications that had formerly been coded in assembly language like operating systems or small embedded systems.
Pro C is simple with lesser rules than any other language
C is standardized and it is the go-to language when you have to speed things up.
Pro Ubiquitous
There is a C compiler available for probably every computer system in existence today.
Pro Easy to drop down to assembly
Sometimes you really need to program directly in assembly. C’s ABI and common compiler extensions make this a piece of cake.
Pro If you can't grok C you should not be a professional programmer
It sets an early bar that if you can't hurdle you might as well do something other than programming and not waste any more of your time.
Pro Basic concepts can be applied to accelerate learning any other language
You can easily pivot knowledge learned here and apply it to almost every other language.
Pro Foundational, difficult but important
Learning C will teach valuable skills and transferrable understanding of computing. While learning a scripting language may be easier, students will not understand system constraints and performance problems, nor what features like garbage collection are actually doing in other languages.
Pro Low level langauge
Pro Huge language supports most everything
C++ is a large language with an even larger community and following. It has libraries for every kind of task that is possible to do with C++
Pro Powerful memory management
Allows puting large arrays on the "heap" to avoid "stack overflow".
Pro Teaches fundamental OOP
Teaches you to leverage object oriented programming.
Pro Excellent compiler optimization
Both open source compilers (such as Clang and GCC), and proprietary ones (like Intel's and Microsoft's) are very good at analyzing program flow and program optimization. This is mostly due to the widespread usage of C/C++ applications running everything from mobile/desktop/server Operating Systems, to search engines and webserver software, and the demand for performance.
Pro Teaches problem solving
The great STL is the most powerful Data Structure and Algorithms Library. It would benefit you very much in problem solving, your main main way to love programming. The code is much compact compared to Java and C#. No unnecessary classes are in your way; yet when you need classes they are available unlike C. The code runs very fast.
Pro Teaches low-level programming, but doesn't have as many pitfalls as C
Teaches data types, low-level program flow and the so common C-style syntax while not being as much of a pain as C itself.
Pro STD is often updated
The functionalities keep growing throughout the years. C++11 gave us a soft type of garbage collecting with the smart pointers.
Pro C code can be used in C++ code
Most C code will work as C++.
Pro Faster execution of the same algorithms
Because C++ (and its precursor C) are "lower level" than a lot of popular programming languages they are also faster at executing code than Java or C# which require VMs and garbage collection threads.
Pro Universal, portable, best complexity/efficiency trade-off
Pro Best way to understand algorithms
Pro Has lots of library
C++ is mature and everything has standardized library.
Cons
Con Languages is full of corner cases and undefined behaviors
Undefined behavior in a program can cause unexpected results, making it hard to debug. With UB, program behavior may vary wildly depending on optimization settings. There are many cases that invoke UB, such as signed overflow, invalid dereferences, large integer shifts, uninitialized variables, etc. These serve to frustrate novice programmers when they could be learning other concepts.
Con Requires memory management
Learning programming is already hard enough when you don't have to worry about memory leaks.
Con Completely lacks type safety
The C standard library is not type safe, and the language itself does not promote type safety built into the language, which leads to error-proneness of the language. If anything, it would be recommended that those interested in C to instead put their time in D, which actually includes a complete copy of the C standard library rewritten to be fully type safe.
Con C will require you to learn concepts too advanced for most beginners
While other programmers will learn algorithms and structures and will do magic tricks and awesome applications, you will learn trash info that you should know maybe after 5-7 years experience in software development, not earlier. It's like going the first time as a seven year old kid to first school class, and your teacher tells you to learn you about Discrete Math, without basic math and how to do 2x2.
If you wish to be a really good programmer, C for sure will be in your portfolio, but not as a first language, and this programming language is used only for very hard and very limited tools which require a lot of professional skills from the programmer.
Con Does not support modules; header file annoyances
Header files are a poor man's implementation of modules. Modern programming languages make use of modules which eliminate the need for C includes and header files and the many issues caused by them, such as the complete lack of dependency checking. Header files often contain even more include statements that point to other header files which also point to even more which drastically increases compile time. Modules only have to be compiled once, and when importing those modules into your software project, you only have to pull in the module that you are using, which is often times already precompiled. This way, the compiler knows exactly what it needs before beginning to compile your project and can automatically compile the few dependencies it needs in advance rather than recursively compiling every header file it runs across as in C.
Con Steep learning curve
While the language compliments knowledge of computer components very well, and gives a deeper understanding, it is also quite difficult to learn, and to use correctly, especially without aforementioned knowledge.
Con Low-level
Depending on the purpose this can be either a pro or a con. If the task is to learn how to program, low-level of C will impend learning important concepts. Furthermore, C is rather limited in ways of building abstractions.
"Low-levelness" of C can be a pro feature in learning system programming.
Con Other languages can do it easier or better
There are languages like Rust, Object Pascal, D, Golang, Vlang, Odin, Zig, Jai, etc... that can be used instead. The other languages are easier to understand, use, and/or about as fast.
Con Compiles procedurally rather than intelligently
In the same manner that C recursively compiles header files ad infinitum without any sort of dependency checking, C source code is also compiled in the same manner. If you attempt to call a function before it is declared, the compiler will fail because the function was not compiled before it was caled.
Con Lack of support for first class strings
C does not support the string type, nor does it support UTF-8 strings that modern languages are employing today. Instead of strings, C makes use of the *char type which is a pointer to a character array.
Con Arrays are not first class objects
When an array is passed to a function, it is converted to a pointer, even though the prototype confusingly says it's an array. When this conversion happens, all array type information gets lost. C arrays also cannot not be resized, which means that even simple aggregates like a stack are complicated to implement. C arrays also cannot be bounds checked, because they don't know what the array bounds are.
Con Undefined behaviors and weak limited type safety
Subtle errors can render the entire program "undefined" by the complicated C standard. The standard imposes no requirements in such cases. Thus C compiler is free to ignore the existence of such cases and Bad Things are prone to happen instead. Even experts can't reliably avoid undefined cases in C, so how can beginners be expected to do so? C allows for non-type safe operations such as logic errors, wild pointers, buffer overflow, etc. UB and type safety issues create a large number of bugs and security vulnerabilities.
Con The need for C developers in the current market is very low, and trending downward
Older languages, like C, are no longer in their hay day. Even if you do learn it as your first language, you are only setting yourself up to need to learn another language in the long run. If you want a skill that you can not only learn from, but also potentially build a career on, C should not be your first choice.
Con Isn't truly portable or cross platform
The C programming language is not portable to other operating systems, and even different compilers, because the C language does not provide any reference cross platform libraries or compilers. Different platforms and compilers provide their own implementation of the C standard library which may not be compatible with the implementation in another compiler or platform. Without cross platform libraries and tools, one cannot state that C is portable. This is in stark contrast to modern programming languages that provide their own cross platform libraries and compilers, such as D, Go and Rust.
Con Only offers basic support for source code split into multiple files
Modern programming languages are capable of compiling split source code files by concatenating them together efficiently at compile time before compiling them. However, C requires the developer to resort to messing with header files and makefiles to get similar functionality.
Con C structs are very weak and outdated
C structs lack a lot of modern capabilities that are vital in programming languages of today, such as assigning member functions to structs to give them object-oriented capabilities, constructs, deconstructors and RAII. Great care must be used when using structs in C to prevent memory leaks and ridiculously slow structs.
Con Includes require obscene resources to compile
All the modern languages have resulted in ditching the ancient deprecated model of #include statements and have instead adopted the superior model of modules. When compiling software written in C, the programmer is forced to also compile X headers which contain Y headers which contain Z headers and so forth -- drastically increasing the number of lines that need to be compiled. In order to compile something as simple as "Hello, World", for example, 18K lines of code needs to be compiled. This can be very taxing on RAM and CPU resources, causing compile times to quickly absorb a large portion of the programming process.
Con Heavily outdated programming concepts
C lacks a large majority of programming concepts that modern languages make use of today. The existing functionality of C makes use of outdated and deprecated methodologies which can be of great annoyance to the modern day programmer.
Con Huge language gets in the way of learning
C++ is such an atrociously over-complicated language that its learning curve may get in the way of learning fundamentals. Learning C++ well is a ten-year project, and even experts are frequently surprised by the language.
Con Tough to learn as the first language
Many of the concepts are hard to grasp if you have no prior programming experience.
Con Undefined behavior
Subtle errors can render the entire program "undefined" by the complicated C++ standard. The standard imposes no requirements in such cases. Thus C++ compiler writers are free to ignore the existence of such cases and Bad Things are prone to happen instead. Even experts can't reliably avoid undefined cases in C++, so how can beginners be expected to do so?
Con Module system is not great
C++ uses the #include
mechanism provided by C. Which unfortunately is a poor way of accessing the API of a library. Some of the reasons why the module system is weak are:
Compile time scalability: The compiler must preprocess every header included in a file, and every header included in those headers. This process must be repeated for every translation unit in the program. As can be imagined, this doesn't scale very well. For each header added you are increasing the compilation time exponentially.
Fragile: modules included are treated as textual imports by the compiler. This causes all sorts of problems since they are subject to any macro definitions in the time of the inclusion. If any of these macro definitions collide with a name in the library it can break the library API .
Con C++ succombs under its own weight
The years of cramped backward compatibility start to show in the syntax, complexity and very top-heavy language structures. Trying to keep up with far more elegant languages like C# doesn't do C++ any good either, because the committee always seems to be able to mess it up. After numerous years, still no modules... you must be kidding!
Con Painfully slow compilation
Beginners need fast feedback
Con Duplicates C features in incompatible ways
Arrays, strings, pointers, etc. have both C and C++ versions. Sometimes the C++ versions are worse. This is more useless trivia beginners have to sort through.
Con Undefined behaviors and weak limited type safety
Undefined behavior in a program can cause unexpected results, making it hard to debug. With UB, program behavior may vary wildly depending on optimization settings. There are many cases that invoke UB, such as signed overflow, invalid dereferences, large integer shifts, uninitialized variables, etc. C++ allows for non-type safe operations such as logic errors, wild pointers, buffer overflow, etc. UB and type safety issues create a large number of bugs and security vulnerabilities.
Con No two programmers can agree on which 10% subset of C++ to use
C++ is such a huge and complicated language, that programmers have to learn a disciplined subset of it to reliably get anything done. The problem is, no-one can agree on which subset to use and they can't understand each other.
Con Retains nearly all bad habits of C
Con No reflection
C++ objects are frustratingly opaque. This makes debugging especially difficult, something beginners have to do a lot.
Con Memory leaks and segmentation faults
Because C and C++ allow the user direct access to memory and don't provide garbage collection threads, there is a probability that a program may have a "memory leak", which occurs when something a programmer allocated in the heap is not deallocated properly. Also, attempting to dereference memory protected by the operating system causes a segmentation fault and kills the program.
Con Arcane binding rules
Con Incomprehensible operator overloading resoution
Con After all these years of trying, still no decent string library.
Although you have several ways to handle strings, all of them are messy and error-prone, giving birth to many crashes and memory corruptions in the field. It's one of the worst languages ever, if you have to do strings.
Con Bugs easily corrupt the memory you need to find them
You can usually get a core dump, but often the call stack gets completely overwritten. Compilers are not even consistent in how they map the binary objects to code.
Con No way to locate definitions
No modules, just files, and no way to tell where anything came from.